Ascidians (IMAGE) University of California - Davis Caption A mix of non-native and native colonial ascidians compete for space on a settlement plate as part of a scientific study. Credit Ben Rubinoff, UC Davis Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. No derivatives or adaptations of the work are permitted. License CC BY-NC-ND Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.